even when you switch to the forum there is absolutely not clear in which topics are new posts...

or am i too dump to see it ?

It's not my first choice either, but thank you to Bitmask for getting something here other than that snow blind default PHPBB theme and for rebuilding the front page so we can get the latest 10 messages showing again. As for for why the change happened, there are some factors involved.

1st, the development team at PHPBB made changes in their software that broke all themes and extensions with their software. So everyone that develops for PHPBB needs to update their products.

2nd, I don't believe the old forum theme, called Solaris, is updated by it's author anymore. I've reached out to him and sent an message through his sites contact form.